Sealing Bag

ABSTRACT

A sealing bag includes a valve  3  which is fitted to a bag body and which communicates interior and exterior of the bag body with each other. A ball valve element  5  of the valve  3  is placed in a tapered passageway  8  so as to be advanceable toward and retreatable from the interior side of the bag body, and can close the tapered passageway  8 . A screw type cap  6  of the valve  3 , which is fitted to a fitting hole  27  of a valve body  4  so as to be advanceable toward and retreatable from a smaller-diameter end portion of the tapered passageway  8 , has a stopper portion which is to be inserted into the fitting hole  27  and contactable with the ball valve element  5.

TECHNICAL FIELD

The present invention relates to a sealing bag which allows such articles as quilts or bedclothes, clothes and foods to be contained therein in a negative-pressure state and compressed.

BACKGROUND ART

Conventionally, there have been available sealing bags which allow various types of articles such as foods to be contained therein and compressed compact. For instance, International Publication of WO 2005/090179 describes a sealing bag as shown in FIG. 21. This sealing bag includes a bag body 301 made from plastic or polyethylene, and a slider 350 slidably fitted to an edge portion of the bag body 301, where an opening portion 307 is provided at an edge portion of the bag body 301.

A pair of interlocking mechanisms 302 are provided at the opening portion 307. When the interlocking mechanisms 302 are engaged together, the opening portion 307 is closed so as to be sealed. Then, when the interlocking mechanisms 302 are disengaged from each other, the opening portion 307 is opened, allowing foods as an example to be put in and out through the opening portion 307. Such engagement and disengagement of the interlocking mechanisms 302 is fulfilled by sliding of the slider 350.

In the slider 350, as shown in FIG. 22, a passageway 308 for communicating the interior of the bag body 301 and the exterior of the bag body 301 with each other is provided. The diameter of the passageway 308 is constant from the interior side of the bag body 301 to the exterior side of the bag body 301. That is, a passageway-defining surface that forms the passageway 308 is cylindrical-shaped.

Within the passageway 308, a spherical-shaped ball valve element 305 is placed. Thus, after air within the bag body 301 is drawn out of the bag body 301, the ball valve element 305 prevents outside air from entering into the bag body 301 through the passageway 308.

The ball valve element 305, which is advanceable and retreatable to the interior side of the bag body 301, can close the passageway 308 by making linear contact with a valve seat provided on the passageway-defining surface.

However, with the above-described conventional sealing bag, since the seal by the ball valve element 305 is a line seal by line contact, the ball valve element 305 is low in seal performance.

Therefore, even if the air within the bag body 301 is drawn out of the bag body 301 so that the bag body 301 is compressed, an elapse of long time would permit outside air to enter into the bag body 301 through between the valve seat and the ball valve element 305, causing the bag body 301 to be decompressed.

That is, the above-described conventional sealing bag has a problem that the airtight state of the bag body 301 cannot be maintained over a prolonged period.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to provide a sealing bag capable of maintaining its airtight state reliably over a prolonged period.

In order to solve the above object, a sealing bag of the present invention comprises:

a bag body which has an opening portion for allowing contents to be put in and out and which is made from a material impervious to fluid;

a sealing mechanism which is provided on the bag body and which can open and close the opening portion, wherein the sealing mechanism, when closing the opening portion, seals the opening portion; and

a valve which is fitted to the bag body and which can communicate interior of the bag body and exterior of the bag body with each other, wherein

the valve includes:

a valve body having a tapered passageway which is tapered increasingly toward an interior side of the bag body, and a fitting hole provided at a proximity to a larger-diameter end portion of the tapered passageway so as to communicate with the tapered passageway;

a valve element which is placed in the tapered passageway so as to be advanceable toward and retreatable from the interior side of the bag body and which can close the tapered passageway; and

a cap having a stopper portion which is inserted into the fitting hole and contactable with the valve element, and a connecting port which communicates with the tapered passageway, the cap being fitted to the fitting hole so as to be advanceable toward and retreatable from a smaller-diameter end portion of the tapered passageway, and wherein

the stopper portion is brought into contact with the valve element closing the tapered passageway as the cap is advanced toward the smaller-diameter end portion of the tapered passageway.

When the sealing bag of this construction is used, a content is first put into the bag body through the opening portion, and thereafter the opening portion is closed and sealed by the sealing mechanism.

Then, the cap is retreated in such a direction as to go farther from the valve body, and thereafter a suction port of a suction pump that sucks air as an example is connected to the connecting port of the cap, in which state the suction pump is operated. Then, the air in the bag body is sucked into the suction pump via the tapered passageway of the valve body. When this occurs, the valve element has moved in such a direction as to be farther from the bag body by the suction force (negative pressure) of the suction pump as well as the air flow, causing a gap to be generated between a tapered circumferential surface defining the tapered passageway and the valve element, so that the air flows toward the suction pump through this gap.

With the suction of the fluid in the bag body still continued, the interior of the bag body goes negative pressure, so that the bag body is compressed by pressure of outside air together with the content.

Then, as the suction port of the suction pump is removed from the connecting port of the cap, the valve element is advanced toward the smaller-diameter end portion in the tapered passageway by the negative pressure inside the bag body. As a result, an outer circumferential surface of the valve element comes into contact with the tapered circumferential surface defining the tapered passageway, with the tapered passageway closed by the valve element.

Thereafter, the cap is advanced toward the smaller-diameter end portion of the tapered passageway. As a result, the stopper portion of the cap comes into contact with the valve element that closes the tapered passageway.

Accordingly, the closed state of the tapered passageway can be prevented from being released, that is, the closed state of the tapered passageway can be maintained. Thus, the tapered passageway can be kept sealed reliably over a prolonged period.

As a consequence, outside air can be prevented over a prolonged period from entering into the bag body through the tapered passageway, so that the airtight state of the bag body can be maintained reliably over a prolonged period.

In one embodiment, the valve body has a claviformed passageway which adjoins the smaller-diameter end portion of the tapered passageway and which is claviformed increasingly toward the interior side of the bag body.

In this embodiment, since the claviformed passageway, which is claviformed increasingly toward the interior side of the bag body, adjoins the smaller-diameter end portion of the tapered passageway, the air in the bag body, when sucked, is guided smoothly to the tapered passageway via the claviformed passageway.

Thus, suction of the air from within the bag body can be achieved with high efficiency, making it possible to reduce the time required for the suction of the air.

In one embodiment, the cap has a fall preventing portion for preventing the cap from falling off from the valve body.

In this embodiment, since the fall preventing portion is included in the cap, the cap can be prevented by the fall preventing portion from falling off from the valve body even when the cap is retreated in the direction for going farther from the valve body.

Accordingly, the user is allowed to retreat the cap in the direction for going farther from the valve body without anxiety.

In one embodiment, the valve element is formed from a material softer and more elastic than a material of the valve body.

In this embodiment, since the valve element is formed from a material softer and more elastic than the material of the valve body, the valve element can be elastically deformed so that the outer circumferential surface of the valve element can be put into planar contact with the tapered circumferential surface that defines the tapered passageway. As a result, a high sealability can be obtained.

Also since the valve element is formed from a material softer and more elastic than the material of the valve body, the valve element, by being elastically deformed, can be reliably held by the tapered circumferential surface that defines the tapered passageway.

Further, since the valve body is formed from a material harder and less elastic than the material of the valve element, the valve body, even if fixed to the bag body by thermo-compression, can be prevented from deformation.

In one embodiment, the cap is formed from a material softer and more elastic than a material of the valve body.

In this embodiment, since the cap is formed from a material softer and more elastic than the material of the valve body, inserting the suction port of the suction pump into the connecting port of the cap causes the connecting port to be elastically deformed into close contact with the suction port of the suction pump, so that the suction pump can suck up air or the like through the connecting port with reliability.

In one embodiment, the bag body includes:

a bag-front-side sheet on which the valve is fitted at an edge portion thereof;

a bag-rear-side sheet opposed to the bag-front-side sheet; and

a gusset which couples the bag-front-side sheet and the bag-rear-side sheet to each other and which is bent inward.

In this embodiment, when the bag-rear-side sheet is positioned below the bag-front-side sheet, liquid in the bag body is accumulated on the bag-rear-side sheet. In this state, if the suction port of the suction pump that sucks gas as an example is connected to the connecting port of the cap, followed by operating the suction pump, then by virtue of the arrangement that the valve is fitted at an edge portion of the bag-front-side sheet, only the gas present between the bag-front-side sheet and the liquid within the bag body can be drawn out of the bag body.

According to the sealing bag of the present invention, since advancing the cap toward the smaller-diameter end portion of the tapered passageway causes the stopper portion to come into contact with the valve element that closes the tapered passageway, the closed state of the tapered passageway can be prevented by the stopper portion from being released.

Thus, a high sealability can be obtained over a prolonged period, and the bag body can be maintained in a negative-pressure state reliably over a prolonged period.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view of a sealing bag according to one embodiment of the invention.

FIG. 2 is a schematic enlarged view of a valve in the embodiment;

FIG. 3 is a schematic sectional view of the valve 3 in its closed state.

FIG. 4 is an enlarged view of the interior of a circle S of FIG. 3;

FIG. 5 is a schematic front view of the valve 3 in its opened state.

FIG. 6 is a schematic sectional view taken along a line F6-F6 of FIG. 5.

FIG. 7 is a schematic perspective view of a valve body.

FIG. 8 is a schematic view of the valve body of FIG. 7 as viewed in a direction of arrow A1.

FIG. 9 is a schematic view of the valve body of FIG. 7 as viewed in a direction of arrow A2.

FIG. 10 is a schematic view of the valve body of FIG. 7 as viewed in a direction of arrow A3.

FIG. 11 is a schematic view of the valve body of FIG. 7 as viewed in a direction of arrow A4.

FIG. 12 is a schematic sectional view taken along a line F12-F12 of FIG. 9.

FIG. 13 is a schematic perspective view of a screw type cap in the embodiment;

FIG. 14 is a schematic view of the screw type cap of FIG. 13 as viewed in a direction of arrow A11.

FIG. 15 is a schematic view of the screw type cap of FIG. 13 as viewed in a direction of arrow A12.

FIG. 16 is a schematic view of the screw type cap of FIG. 13 as viewed in a direction of arrow A13.

FIG. 17 is a schematic sectional view taken along a line F17-F17 of FIG. 14.

FIG. 18 is a schematic sectional view of a modification example of the screw type cap;

FIG. 19 is a schematic perspective view of a tapered valve element;

FIG. 20 is a schematic perspective view of a modification example of the bag body of the embodiment;

FIG. 21 is a schematic perspective view of a sealing bag according to a prior art; and

FIG. 22 is a schematic perspective view of a slider according to a prior art.

DETAILED DESCRIPTION OF THE INVENTION

The sealing bag of the present invention will be described in detail below by way of embodiments thereof with reference to the accompanying drawings.

FIG. 1 is a schematic plan view of a sealing bag according to one embodiment of the invention.

The sealing bag, as shown in FIG. 1, includes a bag body 1 having an opening portion 7 for putting food as an example in and out, a fastener 2 provided at an edge portion of the bag body 1, and a valve 3 fitted to an edge portion of the bag body 1. The food is an example of contents. The fastener 2 is an example of a sealing mechanism.

The bag body 1 has a transparent bag-front-side sheet 11, and a transparent bag-rear-side sheet 12 opposed to the bag-front-side sheet 11. Then, the bag-front-side sheet 11 and the bag-rear-side sheet 12 are each made from a material impervious to fluid (e.g., plastic film). Also, an edge portion of the bag-front-side sheet 11 is, in its most part, thermally compressed to an edge portion of the bag-rear-side sheet 12 and, in part, thermally compressed to the valve 3 together with the edge portion of the bag-rear-side sheet 12. It is noted that the thermo-compression is not applied to parts in the edge portions of the bag-front-side sheet 11 and the bag-rear-side sheet 12 where the opening portion 7 is formed.

Unevenness 13 (shown in part only) is formed generally all over the internal surface of the bag-rear-side sheet 12. This unevenness 13, including a plurality of generally circular-shaped protrusions as viewed in plan view, is formed by embossing or other working. Even when the bag-front-side sheet 11 and the bag-rear-side sheet 12 are put into contact with each other, the presence of such unevenness 13 allows gaps to be ensured between the bag-front-side sheet 11 and the bag-rear-side sheet 12 so that fluid such as air or liquid present in the bag body 1 can be drawn out of the bag body 1 from the valve 3. That is, by the unevenness 13, the fluid is never confined within the bag body 1 and incomplete draw-out of the fluid from within the bag body 1 can be prevented.

The fastener 2, which can open and close the opening portion 7 of the bag body 1, seals the opening portion 7 in closure mode. More specifically, the fastener 2 has a male fastener member and a female fastener member opposed to the male fastener member, which are not shown.

The material used for the male fastener member and the female fastener member is made of a plastic having moderate flexibility and elasticity. The male fastener member can be either fitted into the female fastener member or pulled out from the female fastener member. Fitting the male fastener member into the female fastener member causes the opening portion 7 of the bag body 1 to be closed, and pulling out the male fastener member from the female fastener member causes the opening portion 7 of the bag body 1 to be opened.

The valve 3 acts to communicate the interior of the bag body 1 and the exterior of the bag body 1 with each other. The valve 3, as shown in FIG. 2, includes a valve body 4, a generally spherical-shaped ball valve element 5 (see FIGS. 3 and 4), and a screw type cap 6. It is noted that the ball valve element 5 is an example of a valve element and the screw type cap 6 is an example of a cap.

FIG. 3 is a schematic sectional view of the valve 3 in its closed state. FIG. 4 is an enlarged view of a part surrounded by a circle S of FIG. 3.

The valve body 4, as shown in FIGS. 3 and 4, has a tapered passageway 8 which is tapered increasingly toward the right side in the figure (toward the interior side of the bag body 1), a fitting hole 27 provided at a proximity to a larger-diameter end portion of the tapered passageway 8 so as to communicate with the tapered passageway 8, and a claviformed passageway 28 which adjoins a smaller-diameter end portion of the tapered passageway 8 and which is claviformed increasingly toward the right side in the figure (see FIG. 4). The valve body 4 is obtained by molding of PE (polyethylene), PP (polypropylene) or other hard plastics.

The ball valve element 5 is placed within the tapered passageway 8. This ball valve element 5 is formed from a material softer and more elastic than the material of the valve body 4. More specifically, the ball valve element is formed from silicone rubber, nitrile rubber, elastomer, synthetic rubber, biodegradable resin, synthetic resin (e.g., polyisobutylene), or the like.

An annular engaging portion 32 is provided in an inner circumferential surface of the fitting hole 27. This engaging portion 32 is engageable with a seal portion 30A later-described. It is noted that the seal portion 30A is an example of a fall preventing portion.

The screw type cap 6 is fitted to the fitting hole 27 so as to be advanceable toward and retreatable from the smaller-diameter end portion side of the tapered passageway 8 (see FIGS. 5 and 6). Also, the screw type cap 6 has a generally cylindrical-shaped cylindrical portion 29 which is to be inserted into the fitting hole 27, a stopper portion 9 which is provided at a right-side end of the cylindrical portion 29 in FIGS. 3 and 4 so as to be contactable with the ball valve element 5, two annular seal portions 30A, 30B provided in an outer circumferential surface of the cylindrical portion 29 at its right-side end portions in the figures, and a connecting port 31 which adjoins a left-side end portion of the cylindrical portion 29 in the figures so as to communicate with the tapered passageway 8. Then, the screw type cap 6 is formed from a material softer and more elastic than the material of the valve body 4. More specifically, the screw type cap 6 is made from a flexible plastic or the like.

The seal portions 30A, 30B are in contact with the inner circumferential surface of the fitting hole 27. Thus, in the closed state of the valve 3, air leaks from between the inner circumferential surface of the fitting hole 27 and the outer circumferential surface of the cylindrical portion 29 can be prevented.

The seal portions 30A, 30B slide on the inner circumferential surface of the fitting hole 27 as the screw type cap 6 moves relative to the fitting hole 27. Thus, air leaks from between the inner circumferential surface of the fitting hole 27 and the outer circumferential surface of the cylindrical portion 29 can be prevented even during the move of the screw type cap 6.

FIG. 5 is a schematic front view of the valve 3 in its opened state. FIG. 6 is a schematic sectional view taken along a line F6-F6 of FIG. 5.

As the screw type cap 6 in the state shown in FIGS. 3 and 4 is rotated reverse, the screw type cap 6 moves in a direction for going farther from the valve body 4, resulting in a state shown in FIGS. 5 and 6. In this state, the distance between the stopper portion 9 and the tapered passageway 8 becomes longer, as compared with the state shown in FIGS. 3 and 4. Thus, the ball valve element 5 is enabled to move in a direction for going closer to the smaller-diameter end portion of the tapered passageway 8 or move in a direction for going farther from the smaller-diameter end portion of the tapered passageway 8. That is, the ball valve element 5 is advanceable and retreatable within the passageway of the valve body 4 toward and from the interior of the bag body 1 (see FIG. 1).

Also in the state shown in FIGS. 5 and 6, the seal portions 30A, 30B are in contact with the inner circumferential surface of the fitting hole 27. Thus, air leaks from between the inner circumferential surface of the fitting hole 27 and the outer circumferential surface of the cylindrical portion 29 can be prevented even in the opened state of the valve 3.

Further, as the screw type cap 6 is rotated reverse from the closed state, the seal portion 30A becomes engaged with the engaging portion 32. Thus, the screw type cap 6 can be prevented from falling off from the valve body 4.

FIG. 7 is a schematic perspective view of the valve body 4.

The valve body 4, as shown in FIG. 7, has such a configuration as to decrease in thickness gradually from central portion toward both side portions.

FIG. 8 is a schematic view of the valve body 4 of FIG. 7 as viewed in a direction of arrow A1. FIG. 9 is a schematic view of the valve body 4 of FIG. 7 as viewed in a direction of arrow A2. FIG. 10 is a schematic view of the valve body 4 of FIG. 7 as viewed in a direction of arrow A3. Further, FIG. 11 is a schematic view of the valve body 4 of FIG. 7 as viewed in a direction of arrow A4.

On the outer circumferential surface of the fitting hole 27 of the valve body 4, a thread portion 33 is integrally formed as shown in FIGS. 8 to 10. Also, in the valve body 4, two blind holes 15 are formed as shown in FIG. 11, the two blind holes 15 being opened at a lower end face (an end face on the side opposite to the fitting hole 27 side) of the valve body 4.

FIG. 12 is a schematic sectional view taken along a line F12-F12 of FIG. 9.

Surfaces defining the tapered passageway 8 and the claviformed passageway 28 are generally conical-shaped as shown in FIG. 12. More specifically, a taper angle α of the surface defining the tapered passageway 8 is set to 15°-22° (e.g., 18°). On the other hand, a taper angle β of the surface defining the claviformed passageway 28 is set to 18°-35° (e.g., 23°).

The inner circumferential surface of the fitting hole 27 is also generally conical-shaped, the taper angle of the inner circumferential surface being set to 1°-4° (e.g., 2°).

FIG. 13 is a schematic perspective view of the screw type cap 6.

The screw type cap 6, as shown in FIG. 13, has a generally cup-shaped screwing portion 17 formed integrally with the connecting port 31.

FIG. 14 is a schematic view of the screw type cap 6 of FIG. 13 as viewed in a direction of arrow A11. FIG. 15 is a schematic view of the screw type cap 6 of FIG. 13 as viewed in a direction of arrow A12. Further, FIG. 16 is a schematic view of the screw type cap 6 of FIG. 13 as viewed in a direction of arrow A13.

The stopper portion 9, as shown in FIGS. 14 and 16, has a disc portion 18 provided with a through hole 20, and three connecting portions 19 extending radially outward from peripheral edge portions of the disc portion 18. These connecting portions 19 connect the disc portion 18 and the cylindrical portion 29 to each other. Air in the bag body 1 passes through a space of the through hole 20 and a space between the disc portion 18 and the cylindrical portion 29, being directed outward of the bag body 1.

FIG. 17 is a schematic sectional view taken along the line F17-F17 of FIG. 14.

In the inner circumferential surface of the screwing portion 17 is provided a groove 34 with which the thread portion 33 (see FIGS. 8 to 10) is to be screwed. With the thread portion 33 partly screwed with the groove 34, rotating forward the screw type cap 6 causes the thread portion 33 to be entirely screwed with the groove 34, the cylindrical portion 29 entering into the fitting hole 27.

When the sealing bag of this construction is used, food is first put into the bag body 1 through the opening portion 7 shown in FIG. 1, and thereafter the opening portion 7 is closed and sealed by the fastener 2.

Then, the screw type cap 6 is reversely rotated so as to be retreated farther from the valve body 4 until the state shown in FIGS. 5 and 6 is reached. With this state maintained, for example, a suction port of a suction pump (not shown) that sucks air is connected to the connecting port 31 of the screw type cap 6, and thereafter the suction pump is operated. Then, the air in the bag body 1 flows through the claviformed passageway 28, the tapered passageway 8, the cylindrical portion 29 and the connecting port 31 in succession, entering into the suction pump. That is, the suction pump sucks up air in the bag body 1. When this occurs, the ball valve element 5 has moved in such a direction as to be farther from the bag body 1 by the suction force (negative pressure) of the suction pump as well as the air flow, making a gap to be generated between the surface defining the tapered passageway 8 and the ball valve element 5, so that the air flows toward the suction pump through this gap.

With the suction by the suction pump still continued, the interior of the bag body 1 goes negative pressure, so that the bag body 1 is compressed together with the food by the pressure of outside air.

Then, when the suction port of the suction pump is removed from the connecting port 31 of the screw type cap 6, the ball valve element 5 is advanced toward the tapered side in the tapered passageway 8 by the negative pressure inside the bag body 1. As a result, the outer circumferential surface of the ball valve element 5 comes into contact with the tapered circumferential surface defining the tapered passageway 8, with the tapered passageway 8 closed by the ball valve element 5.

Thereafter, the screw type cap 6 is rotated forward so that the stopper portion 9 is advanced toward the smaller-diameter end portion of the tapered passageway 8 until the state shown in FIGS. 2 to 4 is reached. As a result, the stopper portion 9 comes into contact with the ball valve element 5 that closes the tapered passageway 8.

Accordingly, by means of the stopper portion 9, the ball valve element 5 can be prevented from separating away from the tapered circumferential surface defining the tapered passageway 8, so that the closed state of the tapered passageway 8 can be maintained. Thus, it becomes practicable to seal the tapered passageway 8 reliably over a prolonged period.

As a consequence, outside air can be prevented over a prolonged period from entering into the bag body 1 through the tapered passageway 8, so that the airtight state of the bag body 1 can be maintained reliably over a prolonged period.

Further, since the claviformed passageway 28, which is claviformed increasingly toward the interior side of the bag body 1, adjoins the smaller-diameter end portion of the tapered passageway 8, the air in the bag body 1, when sucked, is guided smoothly to the tapered passageway 8 via the claviformed passageway 28.

Thus, suction of the air from within the bag body 1 can be achieved with high efficiency, making it possible to reduce the time required for the suction of the air.

Further, since the ball valve element 5 is formed from a material softer and more elastic than the material of the valve body 4, the ball valve element 5 can be elastically deformed so as to be positioned at a place indicated by a two-dot chain line of FIGS. 3 and 4. When the ball valve element 5 is elastically deformed so as to be positioned at the place indicated by the two-dot chain line of FIGS. 3 and 4 as described above, the outer circumferential surface of the ball valve element 5 can be put into planar contact with the tapered circumferential surface defining the tapered passageway 8, so that a high sealability can be obtained.

Also when the ball valve element 5 is elastically deformed so as to be positioned at the place indicated by the two-dot chain line of FIGS. 3 and 4, the ball valve element 5, by being elastically deformed, can be held reliably by the tapered circumferential surface defining the tapered passageway 8.

Further, since the valve body 4 is formed from a material harder and less elastic than the material of the ball valve element 5, the valve body 4, even if fixed to the bag body 1 by thermo-compression, can be prevented from deformation.

Further, since the screw type cap 6 is formed from a material softer and more elastic than the material of the valve body 4, inserting the suction port of the suction pump into the connecting port 31 of the screw type cap 6 causes the connecting port 31 to be elastically deformed into close contact with the suction port of the suction pump, so that the suction pump can suck up air or the like through the connecting port 31 with reliability.

The above-described sealing bag is useful particularly for cases in which hard contents such as frozen meat are contained in the bag body 1. As to the reason of this, in such a case, even if the suction pump sucks air from within the bag body 1, the negative pressure in the bag body 1 cannot be increased higher, so that the force acting on the ball valve element 5 does not become larger.

In the above embodiment, the unevenness 13 is formed only in the inner surface of the bag-front-side sheet 11. However, unevenness similar to the unevenness 13 may be formed in the inner surface of the bag-rear-side sheet 12 as well, or otherwise unevenness may be formed in the inner surfaces of both bag-front-side sheet 11 and bag-rear-side sheet 12. That is, the unevenness 13 has only to be formed in the surface of at least one of the bag-front-side sheet 11 and the bag-rear-side sheet 12.

Although the protrusions of the unevenness 13 are formed in a generally circular shape in plan view in the above embodiment, yet those protrusions may be formed also in a generally polygonal shape in plan view.

Although the screw type cap 6 having the cylindrical portion 29 is used in the above embodiment, yet a screw type cap 106 having a cylindrical portion 129 shown in FIG. 18 may also be used.

The length of the cylindrical portion 129 in its insertion direction is larger than that of the cylindrical portion 29. Therefore, by rotating forward the screw type cap 106, a stopper portion 109 provided at a tip end of the cylindrical portion 129 can be put into contact with the ball valve element 5 and moreover the ball valve element 5 can be pushed into the interior side of the bag body 1.

Pushing the ball valve element 5 into the interior side of the bag body 1 as shown above causes a connecting portion, i.e. bent portion, between the tapered passageway 8 and the claviformed passageway 28 to bite into the ball valve element 5. As a result, the ball valve element 5 can be held firmly by the bent portion.

Although a generally spherical-shaped ball valve element 5 is used in the above embodiment, yet a solid, generally bullet-shaped tapered valve element 105 as shown in FIG. 19 may also be used. When this tapered valve element 105 is used, an end face of the tapered valve element 105 on its larger-diameter end portion side is opposed to the stopper portion 9. Also, the tapered valve element 105 may be used together with the screw type cap 106.

Although the valve body 4 in which the tapered passageway 8 and the claviformed passageway 28 are formed is used in the above embodiment, yet a valve body in which the tapered passageway 8 only is formed may also be used.

Although the claviformed passageway 28, which is claviformed increasingly toward the interior side of the bag body 1, is connected to the smaller-diameter end portion of the tapered passageway 8 in the above embodiment, yet a passageway whose diameter is generally constant may also be connected to the smaller-diameter end portion of the tapered passageway 8. That is, a passageway defined by a generally cylindrical-shaped surface may be provided so as to adjoin the smaller-diameter end portion of the tapered passageway 8.

Although the valve 3 is fitted to the bag body 1 in the above embodiment, yet the valve 3 may also be fitted to a bag body 201 shown in FIG. 20.

The bag body 201 includes a bag-front-side sheet 211 having the valve 3 fitted at an edge portion thereof, a bag-rear-side sheet 212 opposed to the bag-front-side sheet 211, and a gusset 222 which couples the bag-front-side sheet 211 and the bag-rear-side sheet 212 to each other and which is inwardly bent.

Thus, since the valve is fitted at an edge portion of the bag-front-side sheet 211, it becomes practicable to draw only the gas, which is present between the bag-front-side sheet 211 and the liquid within the bag body 201, out of the bag body 201.

In the above embodiment, a slider for fulfilling the opening and closing of the opening portion 7 easily and reliably may also be fitted to the bag body 1.

Further, the valve structure described in the above embodiment may be provided on the slider of FIGS. 21 and 22.

The configuration of the tapered passageway of the present invention is not limited to such a generally conical shape as in the above embodiment, and any configuration will do only if it is tapered increasingly toward the interior side of the bag body. For instance, the tapered passageway of the invention may be one having a spheroidal shape. 

1. A sealing bag comprising: a bag body which has an opening portion for allowing contents to be put in and out and which is made from a material impervious to fluid; a sealing mechanism which is provided on the bag body and which can open and close the opening portion, wherein the sealing mechanism, when closing the opening portion, seals the opening portion; and a valve which is fitted to the bag body and which can communicate interior of the bag body and exterior of the bag body with each other, wherein the valve includes: a valve body having a tapered passageway which is tapered increasingly toward an interior side of the bag body, and a fitting hole provided at a proximity to a larger-diameter end portion of the tapered passageway so as to communicate with the tapered passageway; a valve element which is placed in the tapered passageway so as to be advanceable toward and retreatable from the interior side of the bag body and which can close the tapered passageway; and a cap having a stopper portion which is inserted into the fitting hole and contactable with the valve element, and a connecting port which communicates with the tapered passageway, the cap being fitted to the fitting hole so as to be advanceable toward and retreatable from a smaller-diameter end portion of the tapered passageway, and wherein the stopper portion is brought into contact with the valve element closing the tapered passageway as the cap is advanced toward the smaller-diameter end portion of the tapered passageway.
 2. The sealing bag as claimed in claim 1, wherein the valve body has a claviformed passageway which adjoins the smaller-diameter end portion-of the tapered passageway and which is claviformed increasingly toward the interior side of the bag body.
 3. The sealing bag as claimed in claim 1, wherein the cap has a fall preventing portion for preventing the cap from falling off from the valve body.
 4. The sealing bag as claimed in claim 1, wherein the valve element is formed from a material softer and more elastic than a material of the valve body.
 5. The sealing bag as claimed in claim 1, wherein the cap is formed from a material softer and more elastic than a material of the valve body.
 6. The sealing bag as claimed in claim 1, wherein the bag body includes: a bag-front-side sheet on which the valve is fitted at an edge portion thereof; a bag-rear-side sheet opposed to the bag-front-side sheet; and a gusset which couples the bag-front-side sheet and the bag-rear-side sheet to each other and which is bent inward. 